Could AI robots replace human astronauts?

On Christmas Eve, an autonomous spacecraft flew past the Sun, closer than any human-made object. Looking into space, NASA’s Parker Solar Probe was on a mission to study more about the Sun, including how it affects Earth’s climate.

It was a time well known to mankind – but one without any direct human involvement, when a spaceship carried out pre-programmed tasks on its own as it passed the sun, without communicating with Earth.

Robotic probes have been sent across the solar system for the past six decades, reaching places that humans cannot. During his 10-day tripThe Parker Solar Probe had a temperature of 1000C.

But the success of these autonomous flights — and the rise of new artificial intelligence — raises the question of what role humans will play in space exploration in the future.

Some scientists question whether astronauts will ever be needed.

“Robots are developing rapidly, and the issue of human deployment is shrinking all the time,” said Lord Martin Rees, the UK’s Astronomer Royal. “I don’t think taxpayer money should be used to send people into space.”

They also talk about the danger of people.

“The only crime is to send people [there] it’s like a trip, something that happens to rich people, and it should be paid for privately,” he says.

Andrew Coates, a scientist at University College London, agrees. “A lot of space exploration, I’m really interested in robotics,” he says. “[They] go further and do more things.”

They are also cheaper than people, he argues. “And as AI advances, robots can become smarter and smarter.”

But what does this mean for the future generations of astronauts who are still on the rise – and there are some jobs that humans can do in space but which robots, even if they advance, can’t?

Robotic spacecraft have visited all the planets around the sun, as well as many asteroids and comets, but humans have only been to two places: the orbit of the earth and the moon.

Altogether, about 700 people have gone into space since the beginning of 1961, when Yuri Gagarin of the then Soviet Union became the first person to explore the universe. Most of these have been orbiting (around the Earth) or suborbiting (short vertical jumps into space for endless minutes, on vehicles like the US company Blue Origin’s New Shepard rocket).

“Popularity will be the reason for human habitation in space,” says Dr Kelly Weinersmith, a biologist at Rice University in Texas and co-author of A City on Mars. “It seems to have come together as a good way to show that your politics are effective and your people are smart.”

But in addition to the innate desire to explore, or to seek fame, people also do research and test the ways of the world, such as the International Space Station, and use this to advance science.

Robots can help with this scientific research, with the ability to travel to unmanned areas, where they can use tools to study and explore the atmosphere and conditions.

“Humans are very flexible and we can do things faster than a robot, but we are tough and expensive to survive in space,” says Dr Weinersmith.

In her 2024 Booker Prize-winning book Orbital, author Samantha Harvey makes it clear: “A robot has no need for water, nutrients, excretion, sleep… It wants and asks for nothing.”

But there are downsides. Most robots are slow and maneuverable – for example on Mars, rovers (remotely operated vehicles) can barely move at 0.1mph.

“AI can beat humans at chess, but does that mean it will be able to beat humans at spatial exploration?” asks Dr Ian Crawford, a planetary scientist at the University of London. “I don’t think we know.”

However, he believes that AI algorithms can make rovers “more efficient”.

Technology can play a role in fulfilling human spaceflight by freeing astronauts from other tasks to focus on important research.

“[AI could be used to] “Exercises are boring,” explains Dr Kiri Wagstaff, a computer and planetary scientist in the US who previously worked at NASA’s Jet Propulsion Laboratory in California. “In the world, people get bored and stop looking, but machines don’t.”

The problem is that a lot of power is needed to use systems like large-scale linguistics (LLM), which can understand and synthesize human language when processing large amounts of data. “We haven’t yet been able to run the LLM on the Mars rover,” says Dr Wagstaff.

“The rovers’ processors are about one-tenth that [of the speed] what your smartphone has” – meaning they can’t handle the rigors of running an LLM.

A complex humanoid machine with arms and legs is another technology that can perform basic tasks in space, mainly because it closely mimics human capabilities.

NASA’s Valkyrie robot was developed by the Johnson Space Center to compete in the 2013 robotics challenge. Weighing 300lb and standing at 6ft2in, it doesn’t look unlike a Star Wars Stormtrooper, but it’s one of a growing number of human-like machines with superhuman powers.

Long before Valkyrie was created, NASA Robot he was the first humanoid robot designed to be used in space, performing tasks that were otherwise performed by humans.

Its specially designed hands mean it can use the same tools as astronauts and perform complex, rigid tasks like holding objects or flipping switches, which have been difficult for other robotic systems.

A future version of Robonaut was flown to the International Space Station on the Discovery shuttle in 2011, where it assisted in maintenance and repair.

“If we need to replace a small part or clean a solar panel, we can do it automatically,” said Dr Shaun Azimi, head of the robotics technology group at NASA’s Johnson Space Center in Texas. “We see robots as a way to protect the environment when people aren’t there.”

He said that robots could be useful, not to replace human researchers but to work alongside them.

Some robots are already working on other uninhabited planets, and sometimes they make their own decisions. NASA’s Curiosity rover, for example, is search an area called Gale Crater on Mars that does some of its science without human intervention.

“You can direct the rover to take pictures of what’s going on, look for rocks that match what the science needs to do, and then fire its laser at that location,” says Dr Wagstaff.

“It can read a specific stone and send it to Earth while people are still asleep.”

But the capabilities of rovers like Curiosity are limited because of their slow motion. And there is something else that they cannot compete with. That is, humans have the added bonus of inspiring humanity back to Earth in a way that machines cannot.

“Inspiration is an intangible,” argues Prof Coates.

Leroy Chiao, a retired NASA astronaut who flew three flights into space in the 1990s and 2000s on NASA’s Space Shuttle and the International Space Station, agrees. “People connect when people are doing something.

“A lot of people are excited about robotic missions. But I would expect the first man on Mars to be bigger than the first moon landing.”

Humans have not traveled further than Earth’s orbit since December 1972, when the last Apollo mission visited the Moon. NASA hopes to return humans there this decade with its Artemis program.

The next job we will see four astronauts fly around the Moon in 2026. Another mission, planned for 2027, will see NASA astronauts land on the surface of the Moon.

Meanwhile, China’s space agency also wants to send astronauts to the Moon.

Elon Musk, the CEO of the US company SpaceX, has his own plans for space. He has said that his long-term plan is to create a colony on Mars, where humans can the world.

His idea is to use the Starship, a new supercar his company is developing, to carry up to 100 people at a time, with the goal of being a million people on Mars in 20 years.

Dr Weinersmith explains: “Musk is arguing that we should move to Mars because that would be a backup for humanity in case of a disaster on Earth,” explains Dr Weinersmith. “If you buy that argument, then sending people into space is important.”

However, there are still great unknowns about living on Mars, including many technical challenges that are said to be unresolved.

“Maybe babies won’t grow up in those places,” he says. “There [are] ethical questions [like this] that we have no answers.

“I think we should slow down.”

Lord Rees has a vision of his own, how human and robotic research can involve humans playing a part in tackling the most difficult areas. “I can imagine that they will use all the techniques of genetic modification, cyborg augmentation, etc., in order to cope with the most difficult environment,” he says.

“We could have new species that would enjoy living on Mars.”

Until then, however, humanity will continue its slow journey into the cosmos, on a path blazed by robotic explorers.

Top image credit: NASA

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